With development of the mobile Internet and popularization of intelligent terminals, data traffic increases rapidly. Because of advantages of a high rate and low costs, a wireless local area network becomes one of mainstream mobile broadband access technologies. In an existing Wi-Fi system, for example, a conventional system based on IEEE 802.11a, a high-throughput system based on IEEE 802.11n, or a very-high-throughput system based on IEEE 802.11ac, uplink data transmission is always point-to-point transmission, that is, on a same channel or in a same spectrum, only one station transceives data to an access point at a same time. Similarly, downlink data transmission is also point-to-point transmission, that is, on a same channel or in a same spectrum, an access point transceives data to only one station at a same time.
In a next-generation Wi-Fi (Wireless Fidelity, wireless local area network) system, for example, a HEW (high efficiency WLAN) system, higher requirements are imposed on a service transmission rate of a wireless local area system. However, limited by a single channel or a single frequency band, the existing point-to-point transmission manner cannot meet the high-speed service transmission requirement.